Day 18 Click to validate API specification

Sorry, if I am missing something really obvious but I can’t work out what I am meant to do for step 3 of this exercise. Where is the Develop tab with the Click to validate option?

Hi, just to say this was also confusing for me too. I can only assume its a case of the current UI not matching the possibly outdated instructions and references in the challenge. Maybe someone from pm can clarify/confirm.